Beyond being incredibly fun, not much can be said about the Hole with certitude.

One of the world's tallest, oldest, and most disgusting chocolate cascades.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

A slice of central Asia in the middle of Berlin.

Once the most densely populated place in the world, this island is now a ghost town.

Furniture tries to escape an abandoned building in San Francisco.

Centuries-old bridges grown from tangled roots.

Walk through living pictures and music in the Cathedral of Images.

It houses the remains of a 17th-century version of the Titanic.

Monasteries on rock pillars, once accessible only by frayed ropes.

David Sedaris called it "The greatest shop in the world."

A church of bones, decorated with 40,000 human skeletons.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

An astounding collection of medical specimens, including bits of President Lincoln.

An Amsterdam street lined with antique shops each one dedicated to a different obscure collection.

A spectacular cave and a beguiling lake.

An isolated dive site teeming with cnidarians.

A 100-year-old purveyor of curiosities, curios, and kitsch featuring mummies, shrunken heads, and a Fiji Mermaid.

One of the oldest medical collections in Europe focusing on rare surgical instruments.

Not one, not two, but three natural bridges remain in this captivating spot post-sinkhole.

Panorama exhibition hall in old silent theater with a beautiful backyard garden.

A hospital closed seemingly in the middle of operations, leaving behind fodder for horror films and ghost hunters.

This Italian church is as beautiful as it is common, except for the real skulls decorating the many mannequins inside.

A collection of collections, including an anatomy museum, the “Cabinet of Physics of Alessandro Volta, a museum of natural history, mineral collection, and much much more...